Spark-plug.



J. T. CAMPBELL L H. Y. BILLINGS.

SPARK PLUG.

APPLICAUON FILED ocr. 5, mi.

LQSZT/Q, wanted De@.10,1918.

STE@

Joserrr'fr.' CAMPBELL AND Heywoon Y. Brumes, or MOUNTAIN Lanes, new messe", Assenons To o. s. INTERNAL ooMBUsTioN co., or NEWARK, New masias", A one POBATION OF NEW JERSEY.l A'

nearest-t ,To all 'whom t may Conoco/1.'.

le it knownfthat we, JosEPIrT. CAMP- i-innr, und Hnrwoon Y. BILLINGS, citizens of the United States, and residents'of Moun-i tain Lakes, county of Morris, and State ofy an improved spark plug which is sel-cleaning'by the scrubbing action of the engine gases. I

provision'oi a spark plug; which may be used over very long, intervals` of time `without any substantial` burning awayV ot spark-A nated.

ing' points, and which `Will secure highly efficient ignition action throughout longy period's'ot use. Another objcctot the invention -is the :provision of an interior electrode of such form as to permit the ready iow ofthe high vtension ignitioncurrent directly to a substantially indefinitely large number of sparking regions or gaps/and Whereby'elec- -trical losses by dissipation or likeeauses are.

eiectivelyrprevented. f

Another ob.'r et of the invention is the pro vision'of a plug having a .gas chamber or recesspinfiear of the region where the sparks occur, of `such torni and or' such entrance and exitv that the yexplosion of compressed charges therein aids and accelerates the ignition off the charge-in the cylinder and at. the same -tiine to effectively clean ythe variscoring, pitting or warping;l of thevalves or' other `'parts ofthe engine` due toiinpinging of -said'- flaming charges thereon is elinn- @ther 'objects and aires of the invention,

more or less -speciticitiizni those referred to above, will hcin patobvions and' in lpart pontedoutein Ithey o rse of the :following de iptionot' the. e nent-s, combinations,

arrangements o1. parts-and implications of principles, Iconstitisiting the mvention;` and Another/object of the invention the sienne-PLUG.

l vSpecification of Letters atent. Patente@ no ggj@ y Application nledhctober 5,1917.v Sera1No.194,844. f

the scope of protection contemplated Will be indicated in the vappended claims.

' In the accompanying drawings, wherein we have illust-rated a preerred embodiment of our invention: y

l4`igure l is a central longitudinal cross sec-tional view, thereof; rand Fig. 2 is a horizontal sectional view of the spark plug, taken on line 2-2 of Fig. l.

Referring now to the drawings, wherein similar reference characters refer to similar parts, l indicates the shell of ther spark plug, the same being of the usual cylindrical form,

vthreaded as at 2, so that it may bje screwed intera cylinder and having a shoulder 3, which with the usual gasket forms-a gas tightV joint with the cylinder.

Theeonducting member 4 of the interior electrode is preferably a rod of substantial diameter, Whichis insulated from the outer shelha portion of Which forms the other electrode'. In the present instance this in-` sulation consists of a. portion 5 composed of layers of mica Wound about the rod 4, and these windings of micaarc then surrounded by a plurality of mica Washers 6 firmly compressed together and confined between a shoulder? provided upon the rod Il, anda cap piece 8. Other forms of insulation may, of course, be employed in the relations above specified.

Theinsulatingr material @has preferably a lateral extension 9, adapted to be seated in an angular recess 10 in the shell l, a washer, as at 11, preferably formed of soft metal, 'such as copper, being inserted in the shell l in,- advance of the insertion of the insulat ing material, and a bushing' l2 screwed .into theshell l may be employed to secure all the parts together, a suitable washer or Washers 13 bein inserted between the lower end of the bushing 12, and between it and the upper shoulder of the lateral extension 9. The

Washers 11 and l are employed toma'ke all the parts .astight and to prevent mutilation of the insulation by the bushing 12. l

'Suitable prorision'is made for securing the cable te which current is supplie to thespark plug, as *for example in the torni shown`r a not M is employed for this purpose, the same being threaded upon thel threaded end of the rod 4. All the parts-so described maybe ot the' usual construction .ind may be modified to suit different requirements.

The insulating bodies 5 and 6 are so disposed within the shell 1 that the lower ends thereof terminate short of the end of the shell, and the extension 16 thereof is reduced so that within the shell 1 there is formed a chamber 17, the purpose of which will be apparent hereinafter.

The lower end of the rod l is formed into a hollow substantiallv cone-shaped extension 18, the walls of which iarc downwardly and outwardly, So that the lower edge 19 terminates substantially flush with the exterior surface of the shell 1. This cone-shaped extension 18 is spaced from the lower edge 20 of the shelll son that a spark gap is provided therebetween, the inner lower edge of the shell 1 being preferably beveled or cham-r fered oil as at 21. A chamber 22 is formed in the lower surface of the electrode 18, and suitable openings 23 are provided, which connect the chambers 17 and 22.

We dnd that by constructing a s ark plug in substantially the manner descril ed, at or in the neighborhood of the s ark region, ignition effects are obtained o a most certain and uniform character whereby a completely continuous metal ic path for the current is provided all the way around the shell 1, the narrowest, space between the electrodes being provided between the lower end of the shell 1 and the surface immediately adjacenty the outer periphery of the Haring end of the electrode 18.

It will be noted that the passage-way forming the spark gap between the electrodes extends laterally at substantially vright angles from the longitudinal axis of the spark plug. This disposition of the spark gap is of great advantage since it directs the flow of the ignited charge within the chamber 17 laterally with respect to the spark plug, whereby any impinging of the ignited charge against the valves, or other parts of the cylindeif is eliminated, thereby insuring these parts against scoring, pitting, or warping by the constant action of such ignited charges.

"We have also found that a spark plug constructed substantially as ,above described,

I has a further advantage that leakage and dissipation of high tension current is greatly reduced and effective ignition obtained by reason of the fact that there is no tendency of the plug to foul. This fouling is prevented by reason of the fact that the particles of carbon and other solids which usually collect on electrodes and spark plugs, are not permitted to come to rest in the v neighborhood of the spark gap, but are effectively blown out, inasmuch as the ignitedy charge Within the chamber 17 sweeps out along the flaring upper surface of the electrode 18, and between the edge thereof wall of said electrode is also maintained in a clean condition.

Itwill accordingly be seen that we have Aprovided a spark plug, which is well adapted to attain, among others, all the aims and objects above pointed out, in an exceedingly efficient manner, by reason of the construction as described, the neighborhood of the spark gap is always maintained clean, whereby effective sparks may at all times be had,.and the ignited charges from the spark plug are so directed that they cannot impinge upon any part of the interior of the engine, whereby' the latter might be damaged.

As many changes could be' made in this construction without departing from the scope of the following claims, it is 1ntended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative only and not in a limiting sense.

Having thus described our invention what we claim vas new and desire to secure by Letters Patent is:

1. A spark plug comprising an outer shell, one end of which forms an electrode, there being a chamber formed in the lower end of saidshell, an inner electrode comprising a hollow cone-like member,- the lower end of which lies beneath the lower end ofthe said'shell, and is spaced there from to form a spark gap. y

2. A spark plug comprising an outer shell, one end of which forms an electrode, there being a chamber formed in the lower end of said shell, an inner electrode comprising a hollow cone-like member, the lower end of which flares outwardly and lies directly beneath the lower end of said 'shell and is spaced therefrom to form a spark gap.`

3. A spark plug comprising an outer shell, one end of whichforms an electrode, said shell having a chamber formed in the lower end thereof, an inner electrode comprising a hollow cone-like member which flares downwardly and outwardly so that the lower edge thereof extends underneath the lower edge of said outer electrode and is spaced therefrom to form a spark gap.

4. A spark plug comprising an outer shell, one end of which forms an electrode, said shell having a chamber formed in the lower end thereof, a conducting rod extending through said -shell and insulated therefrom, the lower end of said rod carrying a yelectrode formed neath the edgel of the outer shell,iand is spaced therefrom to form al spark gap, the

latter comprising a narrow passageway extending atsubstantially a right angle to the'longitudinal axis of the spark plug' 5. A spark plug comprising an outer an insulating member extending into said shell, but terminating short of one lend thereof so that a chamber is formed in one end of said shell, a metallic stem extending into said shell, and through said insulating member, the lower end of said stern being of a hollow cone-like formation, .which `lares' outwardly underneath the lower edge of said outer electrode, so as to substantially close said chamber, a passage-way being provided between the lower end of said shell and the flared end of said electrodeto constitute a spark gap, said passage-Way extending in a direction substantially at right angles to the longitudinal plug.

6. A spark` plug comprising an outer shell, one end of a hollow metallic lshell,

vwe have hereto set. our hands, axis of the spark of which -forms an electrode,

there being a chamber formed in the lower end of said shell, an inner electrode comprising a hollow cone-like member the lower` end of which lies beneath the lower end of said Shell. and spaced therefrom to form a spark gap: said inner electrode being provided wit an exterior chamber, and passage ways extending through said inner electrodes and connecting said chambers.

7. A spark plug comprising an outer shell, one end of which forms an electrode,

there being a chamber formed in the lower end of said shellvand an inner electrode comprising a hollow member the walls ofwhich extend downwardly and outwardly so that the lower end thereof lies directly beneath the end of said shell which forms the electrede and is spaced therefrom to form a spark gap.

In testimony that we claim the foregoing, 'this 2nd day of October, 1917.

JosEPH TQ CAMPBELL. Hnrwoon Y. BiLLiNes. 

